National High Magnetic Field Laboratory, Tallahassee, Florida 32310, USA.
Phys Rev Lett. 2013 May 31;110(22):227402. doi: 10.1103/PhysRevLett.110.227402. Epub 2013 May 29.
We perform polarization-resolved Raman spectroscopy on graphene in magnetic fields up to 45 T. This reveals a filling-factor-dependent, multicomponent anticrossing structure of the Raman G peak, resulting from magnetophonon resonances between magnetoexcitons and E(2g) phonons. This is explained with a model of Raman scattering taking into account the effects of spatially inhomogeneous carrier densities and strain. Random fluctuations of strain-induced pseudomagnetic fields lead to increased scattering intensity inside the anticrossing gap, consistent with the experiments.
我们在高达 45 T 的磁场中对石墨烯进行了偏振分辨拉曼光谱研究。这揭示了拉曼 G 峰的一个依赖于填充因子的多分量反交叉结构，它来源于磁激子和 E(2g)声子之间的磁声子共振。这可以用一个考虑了空间非均匀载流子密度和应变影响的拉曼散射模型来解释。应变诱导赝磁场的随机涨落导致在反交叉间隙内散射强度增加，这与实验结果一致。
